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Synthesis and Anti-inflammatory Action of (η-C_5H_5)_2Ti(Sal)_2 and (η-C_5H_5)_2Ti(Clo)_2

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Chemical Research in Chinese Universities 2006年第1期22卷 6-10页

作者： LI Xiu-juan zeng zheng-zhi College of Chemistry and Chemical Engineering Lanzhou University Lanzhou 730000 P. R. China

Two new complexes （Cp）2Ti （Sal）2 and（Cp）2Ti（Clo）2 （Cp=Cyclopentadienyl η^5-C5H5 ）, have been synthesized in anhydrous THF by the reaction of HSal（o-hydroxybenzoic acid, salicylate acid） or HClo[N-（ m-chloro-phenyl） anthranili acid, acidum clofenamicum] with （Cp）2TiCl2 and characterized by means of elemental analyses, IR, H NMR, ^13C NMR, UV and molar conductivity. In complex （Cp）2Ti（Sal）2 or（Cp）2Ti（Clo）2, the oxygen atom of the carboxyl group coordinates to Ti（Ⅳ） in a monodentate manner. The inhibitory action of the complexes on mouse ear tumefaction caused by croton oil and rat foot granulation growth caused by cotton balls is higher than that of the corresponding ligands HSal, HClo and [ （Cp）2TiCl2 ], whereas their toxicity is lower than those of the free ligands.

关键词： Salicylate acid N-(m-Chlorophenyl) anthranilic acid Cyclopentadienyltitanium complexes Anti-in-flammatory

Proton production,regulation and pathophysiological roles in the mammalian brain

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Neuroscience Bulletin 2012年第1期28卷 1-13页

作者： Wei-zheng zeng Tian-Le Xu Neuroscience Division Department of Biochemistry and Molecular Cell Biology Institute of Medical Sciences ShanghaiJiao Tong University School of Medicine Shanghai 200025 China Institute of Neuroscience and State Key Laboratory of Neuroscience Shanghai Institutes for Biological Sciences ChineseAcademy of Sciences Shanghai 200031 China

The recent demonstration of proton signaling in C. elegans muscle contraction suggests a novel mechanism for proton-based intercellular communication and has stimulated enthusiasm for exploring proton signaling in higher organ- isms. Emerging evidence indicates that protons are produced and regulated in localized space and time. Furthermore, identification of proton regulators and sensors in the brain leads to the speculation that proton production and regulation may be of major importance for both physiological and pathological functions ranging from nociception to learning and memory. Extracellular protons may play a role in signal transmission by not only acting on adjacent ceils hut also af- fecting the cell from which they were released. In this review, we summarize the upstream and downstream pathways of proton production and regulation in the mammalian brain, with special emphasis on the proton extruders and sensors that are critical in the homeostatic regulation of pH, and discuss their potential roles in proton signaling under normal and pathophysiological conditions.

关键词： proton extruders proton sensors pH homeostasis proton signaling pH microdomains local accumulation

Denoising Stochastic Progressive Photon Mapping Renderings Using a Multi-Residual Network

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Journal of Computer Science & Technology 2020年第3期35卷 506-521页

作者： zheng zeng Lu Wang Bei-Bei Wang Chun-Meng Kang Yan-Ning Xu School of Software Shandong UniversityJinan 250101China School of Computer Science and Engineering Nanjing University of Science and TechnologyNanjing 210094China School of Information Science and Engineering Shandong Normal UniversityJinan 250358China

Stochastic progressive photon mapping(SPPM)is one of the important global illumination methods in computer *** can simulate caustics and specular-diffuse-specular lighting effects ***,as a biased method,it always suffers from both bias and variance with limited iterations,and the bias and the variance bring multi-scale noises into SPPM *** learning-based methods have shown great advantages on denoising unbiased Monte Carlo(MC)methods,but have not been leveraged for biased *** this paper,we present the first learning-based method specially designed for denoising-biased SPPM ***,to avoid conflicting denoising constraints,the radiance of final images is decomposed into two components:caustic and *** two components are then denoised separately via a two-network *** each network,we employ a novel multi-residual block with two sizes of filters,which significantly improves the model’s capabilities,and makes it more suitable for multi-scale noises on both low-frequency and high-frequency *** also present a series of photon-related auxiliary features,to better handle noises while preserving illumination details,especially *** with other state-of-the-art learning-based denoising methods that we apply to this problem,our method shows a higher denoising quality,which could efficiently denoise multi-scale noises while keeping sharp illuminations.

关键词： denoising stochastic progressive photon mapping(SPPM) deep learning residual neural network

Austenite grain growth of medium-carbon alloy steel with aluminum additions during heating process

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International Journal of Minerals,Metallurgy and Materials 2019年第3期26卷 282-290页

作者： Zi-yi Liu Yan-ping Bao Min Wang Xin Li Fan-zheng zeng State key Laboratory of Advanced Metallurgy University of Science and Technology Beijing Xiangtan Iron & Steel Co. Ltd.of Hunan Valin

In this study, the effects of heating temperature(850–1100°C) and holding time(30–150 min) on the grain growth behavior of austenite in medium-carbon alloy steel were investigated by conducting experiments. The abnormal grain growth and mixed grain structure phenomenon are explained using an equilibrium precipitation phase diagram calculated by Thermo-Calc software package. The Al N particles were observed by field-emission scanning electron microscopy(FESEM), and the amount of AlN precipitations was detected by electron probe microanalysis(EPMA). Based on the research results, it was found that the average grain size of austenite in the test steel increased continuously with the increase of temperature and holding time. Furthermore, the abnormal growth of austenite occurred in the test steel at 950°C, and the heating temperature affected the austenite grain size more significantly. In addition, the decline in the amount of AlN second-phase particle in the test steel, which weakened the "pinning" effect on austenite grain boundaries, resulted in abnormal growth and the development of mixed austenite grain structures. The prediction model for describing the austenite grain growth of medium-carbon alloy steel during heating was established by regression analysis of the experimental data, and the model was verified to be highly accurate.

关键词： alloy steel austenite grain AlN growth model

Diving dynamics identification and motion prediction for marine crafts using field data

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Journal of Ocean Engineering and Science 2024年第4期9卷 391-400页

作者： Yiming Zhong Caoyang Yu Yulin Bai zheng zeng Lian Lian School of Oceanography Shanghai Jiao Tong UniversityShanghai 200030China Key Laboratory of Polar Ecosystem and Climate Change Ministry of EducationShanghai Jiao Tong UniversityShanghai 200030China Shanghai Key Laboratory of Polar Life and Environment Sciences Shanghai Jiao Tong UniversityShanghai 200030China State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China

Ensuring accurate parameter identification and diving motion prediction of marine crafts is essential for safe navigation,optimized operational efficiency,and the advancement of marine *** this,this paper proposes an instrumental variable-based least squares(IVLS)***,aiming to balance complexity with accuracy,a decoupled diving model is constructed,incorporating nonlinear actuator characteristics,inertia coefficients,and damping ***,a discrete parameter identification matrix is designed based on this dedicated model,and then a IVLS algorithm is innovatively derived to reject measurement ***,the stability of the proposed algorithm is validated from a probabilistic point of view,providing a solid theoretical ***,performance evaluation is conducted using four depth control datasets obtained from a piston-driven profiling float in Qiandao Lake,with desired depths of 30 m,40 m,50 m,and 60 *** on the diving dynamics identification results,the IVLS algorithm consistently shows superior performance when compared to recursive weighted least squares algorithm and least squares support vector machine algorithm across all depths,as evidenced by lower average absolute error(AVGAE),root mean square error(RMSE),and maximum absolute error values and higher determination coefficient(R2).Specifically,for desired depth of 60 m,the IVLS algorithm achieved an AVGAE of 0.553 m and RMSE of 0.655 m,significantly outperforming LSSVM with AVGAE and RMSE values of 8.782 m and 11.117 m,***,the IVLS algorithm demonstrates a remarkable generalization capability with R2 values consistently above 0.95,indicating its robustness in handling varied diving dynamics.

关键词： Marine craft Parameter identification Motion prediction Instrumental variable-based least-squares algorithm Diving dynamics model

Molecular Dynamic Studies on Langmuir Monolayers of Stearic Acid

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Chemical Research in Chinese Universities 2013年第3期29卷 545-550页

作者： KONG Chui-peng ZHANG Hong-xing ZHAO zeng-xia zheng Qing-chuan State Key Laboratory of Theoretical and Computational Chemistry Institute of Theoretical Chemistry Jilin University Changchun 130021 P. R. China

Compression isotherm for stearic acid was obtained by means of molecular dynamic simulation and compared to experimentally measured values for the Langmuir monolayers. Compared to the previous simulation, the present simulation has provided a method to reproduce the compression of the monolayer. The result is consistent with other experimental results. By analyzing the alkyl tails, the configuration of stearic acid molecules during the compression process was studied and a uniform monolayer was obtained after compression. Stearic acid molecules were observed to form fine organized monolayer from completely random structure. Hexatic order of the arrangement has been identified for the distribution of stearic acid molecules in the monolayer. At the end of the compression, the stearic acid molecules were tightly packed in the gap of two other molecules. At last, the hydrogen bonds in the system were analyzed. The main hydrogen bonds were from stearic acid-water interaction and their intensities constantly decreased with the decreased of surface area per molecule. The weak hydrogen bond interaction between stearic acid molecules may be the reason of easy collapse.

关键词： Stearic acid Monolayer Molecular dynamics

Expression of ornithine decarboxylase in precancerous and cancerous gastric lesions

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World Journal of Gastroenterology 2007年第20期13卷 2867-2871页

作者： Xin-Pu Miao Jian-Sheng Li Hui-Yan Li Shi-Ping zeng Ye Zhao Jiang-zheng zeng Department of Gastroenterology the Affiliated Hospital of Hainan Medical College Haikou 570102 Hainan Province China Department of Gastroenterology the First Affiliated Hospital of Zhengzhou University Zhengzhou 450052 Henan Province China Department of Chemotherapy for Cancer West China Hospital of Sichuan University Chengdu 610041 Sichuan Province China Department of Cancer the Affiliated Hospital of Hainan Medical College 31 Longhua Avenue Haikou 570102 Hainan Province China

AIM: To investigate the expression of ornithine decarboxylase (ODC) in precancerous and cancerous gastric lesions. METHODS: We studied the expression of ODC in gastric mucosa from patients with chronic superficial gastritis (CSG,n = 32),chronic atrophic gastritis CAG,n = 43; 15 with and 28 without intestinal metaplasia (IM),gastric dysplasia (DYS,n = 11) and gastric cancer (GC,n = 48) tissues using immunohistochemical staining. All 134 biopsy specimens of gastric mucosa were collected by gastroscopy. METHODS: The positive rate of ODC expression was 34.4%,42.9%,73.3%,81.8% and 91.7% in cases with CSG,CAG without IM,CAG with IM,DYS and GC,respectively (P < 0.01),The positive rate of ODC expression increased in the order of CSG < CAG (without IM) < CAG (with IM) < DYS and finally,GC. In addition,ODC positive immunostaining rate was lower in well-differentiated GC than in poorly-differentiated GC (P < 0.05). CONCLUSION: The expression of ODC is positively correlated with the degree of malignity of gastric mucosa and development of gastric lesions. This finding indicates that ODC may be used as a good biomarker in the screening and diagnosis of precancerous lesions.

关键词： Ornithine decarboxylase Gastric carcinoma Precancerous lesions Diagnosis Immunohistochemistry

LARGE DEFLECTION THEORY OF NANOBEAMS

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Acta Mechanica Solida Sinica 2010年第5期23卷 394-399页

作者： Dujuan zeng Quanshui zheng 1(Department of Engineering Mechanics,Tsinghua University,Beijing 100084,China) Department of Engineering Mechanics Tsinghua University Beijing China

One-dimensional nanostructured materials are often used as beams in many applications such as ultrahigh-frequency resonators and ultrasensitive sensors. Compared with usual macroscopic beams, nanobeams have much higher surface/volume ratios so that their surface energies may play a significant role. Besides, they often bear large deflections due to their typically large slenderness ratios and larger elastic ranges. There is, however, lack of a theory that takes into account of both the above two features owned by nanobeams. In this paper, we present such a theory and give applied examples to show that surface energy and large deflection may individually or jointly have notable effects.

关键词： nanobeam surface energy large deflection

MORPHOLOGY AND PERFORMANCE OF UNSATURATED POLYESTER NANOCOMPOSITES MODIFIED WITH ORGANOCLAY AND THERMOPLASTIC POLYURETHANE

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Chinese Journal of Polymer Science 2010年第6期28卷 913-922页

作者： Chang-jiang You Jin-guo Xua Yi-zheng zeng Yao Li De-min Jia Toshio Nishi College of Materials Science and Engineering South China University of Technology Guangzhou 510640 China WPI Advanced Institute for Materials Research Tohoku University 2-1-1 Katahira Aoba Sendai 980-8577 Japan

Unsaturated polyester（UPR）/thermoplastic polyurethane（TPU）/organoclay nanocomposites were prepared by melt compounding of thermoplastic polyurethane and unsaturated polyester prepolymer,and then mixing with the hybrids of styrene monomers and organoclay at ambient *** crosslinking reaction eventually occurred through the unsaturated polyester prepolymer and styrene *** morphology of the composites was investigated by scanning electron microscopy（SEM） and transmission electron microscopy（TEM）.The results show that the impact strength of UPR/TPU/organoclay nanocomposites increases obviously;the cure shrinkage decreases markedly,the glass transition temperature is enhanced and an elastic response to the deformation is prominent at the temperature above 10℃.

关键词： Unsaturated polyester Thermoplastic polyurethane Organoclay Nanocomposites